Mechanical pencil



Feb. 17, 1931. J. MEILNER MECHANICAL PENCIL Fired Dec' 2 Sheets-Sheet 1l ATTORNEY I Z INVENTOR @www Y Feb 17, 1931. J. MEILNER MECHANICAL PENL2 Sheets-Sheet 2 Filed Dec. 4, 1926 MMQ ATTORNEYS .if-klim, kwik ItPatenieaFeb.17,1931

' .uNiTEDsTATEs Y PANY, or Nnw'Yon-K, Y.

, JOSEPH, MEILNEB, or oRANG-Efnnw JERSEY, assierioisf'roy'iiliaise.riiiiioi,L COM; A coeronarion oFDnLAWAREi y Mnoiiariioanrendir.' i

j .Appiieaien inea. Membern-192e. semaine. 152,534. l i 5 This inventionrelates to;mechanical-peneA cils, land has 'particular reference toimprove- Vments inthe mechanism for holding and operating any of thevarious marking mate- Y rials used in vsuch pencils. The term lead 1 isused herein for convenience when referring to such marking material ortoparts associated with it, but that term is intended to include any ofthe v arious materials. ofdifi0 ferent colors which areormayxbeused insubstantially all of each piece of leadz'inV connection with novelprovisions whereby after the last of the lead has been expelled,

a new lead `may be inserted through the writing end of the pencil `andengaged with f a lead carrying mechanism in such away asl to permitmoving the lead in or 'out ofthe pencil asand whendesired. In thepresent embodiment, the lead carrying mechanism comprises two relativelymovable parts, one

L59 of whichis a feeding element such as a'rod:

which is actuated in either direction as 'hereinafter described, andaclutch Or'tube for holding the lead. This clutchY or tube ,will

n hereinafter'be referred to as the carrier tubev or, in some instances,as the carrier. The care` f rierandthe feeding rod are so associatedthat? the carrier will be held stationary in the pen' cil during thelatter part ofthe fullV expelling movement of the feed rod to 'ejectthelast of the lead from the carrier. The carrier is then heldstationary during the forepart of the retracting movement'v of the-feedrod,

thereby clearing the end 'of -the carrier `to- 5 permit the engagementofthe lead with the carrier. *The construction for effecting theserelative-movements of the carrier and the feeding elements is muchsimpler than any prior construction for laccomplishing' the same orsimilar results with whichlapplicant isfamiliar; fandcan be produced atarelaj tively low cost.

Anotherv object `ofthe .invention is lto proV vide a new andyhighlysatisfactoryf'way'of making an operating'screwj-or helix' for mechanicalpencils. 1

The inventionhas vantages which will be apparent fromY this .i

specification and the drawings which accompany and form a' partoffsaidspecification. Y

- In said drawings? y i Fig. .1 is a longitudinal section throughaApencil containing one embodiment of the inf vention.

Fig.`2 shows 0n a largerj'scalefdetails'V of Some of the mechanism shownin Fig. 1': v

`Fig showsfrom a differentangle the same mechanism as is shown inFig-2:- Y

Fig. 4 shows on a largery scale details of the lead Icarrier tube andfeed rod. i'

Fig. 5 is the same as Fig. 4,- 'except that the -Y parts` are showninthe relative positions they assume at the end of theexpellingmovement. Fig. 6 shows a/section on the line 6 6 of Fig; 2. f 1e 'n ig. 7 shows a sectionron line 7-'-7 in Fig. 4.l

yen

Fig.V 8 shows a section'on line 8 8 in Y Fig. A

Figs-9,10 and'rll in detail the fea-V tures of a modified construction;V

Fig. 12 showsdetails of the construction f of the lead carrier andfeedingrelement used. vin the modified form shownin'Figs'. 9, 10V

and 11.

Fig. 13 is a section onthe linelS-l of' Fig. 14 is a section on the line14-1-14 ofk The construction shown in Figs. .1 to 8, inclusive, which''is' the preferred construction, comprises va'bdy 11 Voff'any'materialsuitable for thepurpose. Secured to one end of the body 11 is a sleeve12. yThe-other end of the body 1.1 of the penciliisv provided with Vashell 13 tapered vor shaped in 'any desired manner to the form shown.

The interior of the body llgof the pencil isv tubular fora part ofitslength to accomf modate a t'uhe14 whichffserves as a part'of the drivingmechanism, and may also be used as a container for eXtra leads. tachedto one end of the tube 14 is an element 15 journaled in the sleeve 12. Y4A cup-shaped member 16 containing an ,y eraser 17 is frictionallysupported in the elevment 15 and engaging' With the exterior of themember isa cap 1S which maybe removed When it isf'desired to have accessto the eraser 17 for making erasures or to' permit removal of the member16 and eraserto give accessto the lead storage chamber in the tube 14.It isapparent from the description just giventhat the tube 14, member 15and eraser holder 16 may berotated as a unit -bvturning the cap 18rela-tive to the body 11 of the pencil.

Secured' to one e'nd-of the tube'14` is a split tube21. The tubes 21 and14 are held against endwise movement in one direction in the pencil b ya Washer 22 ,surrounding the tube l21 'and actingfbetweenthe Vend ofthetube 14 and a shoulder onV the interior of the pencil. `Endwise movementof the saine parts kin the :other direction is prevented by a Washer 23and a member having `the appearance of an eyelet which is snugly tted onVthe tube 21 so as :to hold the Washer 22 in engagement with the end ofthe body 11 ofthe pencil. UThe Washers 22 and 23 not only prevent theendwise` movementsmentioned.,butthey alsoserve as bearings.lixingtheaXis of .rotation ofthe tubes 14 and V21. i

Slidably mounted in the split tube 21 isV a vlead carrier tube 27 whichis vpreferably formed of .thin resilient lmaterial and :has an internal`diameter cor-responding closely to the :diameter of the Ilead 2S. lThevcarrier tube 27 is preferably cut away to provide an opening throughWhich projects an operating portion 32 of a lead feed rod 33. The

1 and 2. Not-ches 39 in the portion '.32 l'of the feeding element engageWith a helix-41 on the interior of thepenc'il. By rotating the head 18-relative to fthe bodyof .the pencil, the kengagement of :the.1notches39. With the helix will drive the 'lead feedrrod133 iifn eitherdirection, Yas desired. ATWhen that di-4 rection isthe one which feedsfthe .lead outward of the ipencil, the `head 32 `of the .rod Willcooperate With'the end :40 of a wing 42 formed-on the lead carriertube27 :at'one sideV of :the slot .in the `tube and ycause the `feed rod33 and-'carrierrtube 27 to move asa rveaesvff tinued movement of thefeed rod 33 will' until the end 401 of the Wing 42 engages-the i causethe head 32 to act against the .tend 40 Y of the Wing, which end issuitably V*formed v.to vact as a cam andl thereby move the Wing 42 asideand bring the end 40 Aof Vthe `ivino" -behind a shoulder 46 formed onthe split tube'21 by cutting aWayf the f'split tube as shown at 47. ThemovementA of the feed Yrod 33 Which'e'ects theoperation of the Wing 42Vdescribed ivill-alsocause the rod 33 to move relative to thecarriertube 27 until the end ofthe rod 33-projecfts from the end lof thecarrier tube `27 asshoWn in F ig. 5, thereby ejectinglthe last fof the"lead-from the carrier tube 127 to Areceive `the inserted lead. Y

Continued reverse movement Will Withdraw the head 32`from engagementlWiththe Wing 42 and permit the Wing .to .be disengaged from theshoulder 46 on the split tube, after Which the :carrier tube and'feed-rod move as unit during the rest 'ofthe reverse` or reti-actingmovement, ,so Aas to draw the lead into the.v pencil. l y y rThe Ihelixl41 is Fmadenof Wire of suitable cross-section,resting'in aV helicalgroove on the interior :of the pencil. In manufacturing the pencils .asuitable tool is vfirst lrun through the barrel to out the .helicalgroove and ythe Wire Ylheliai is .then vrun into the g-roove. As aresult, a `durable and otherwise fhighly satisfaotery construction ismade possible. fact, the construction is as satisfactory for allpractical vpurposes ,as Y prior constructions which :cost .a great dealmore. to make.v

rlhe Vmodified construction shown iny Figs.f

9 tto 12,'inclusive, is .the same 'as `the preferred InAk constructionin most respects, the principal differences .being in `the mechanism foreffecting relative.movements of the lead Afeed rodand the,-leadca-rfrier tube.

lIn-.the `mod-itied qconstnuction, the feed irod 50 has a projectiony.5.-1 gengaging between the turns-of the 'helix ,52 and .extend-ingthrough a slot '53,fin 'the lead carrier tube v54 .and a slotr in`rthe'fsplit tube. It is preferred to have the sides vofthe slot 5 3in'frictional engagement fWi-th fthe sides -o-f-the projection 51, thepurpose of the frictional `engagement being to .afford a .means foryieldingly mai-ntaining .the-lead feed rod and the lead carrier tubeindifferent-relative posit-pons. Y mliedseonstructionfthe split 'tube 56is made of resilient material and is preferclutch'ofthe portion ofthersplit tube ad'- jacent the writing end of the pencil.V When the pencilis operated to fully expel alead,

Vthe carrier tube will be driven to the position shown in Fig. 11;During its movement to that position, it will expand the clutch'on thesplit tube, the driving connection for so expanding the clutch beingaoided by engagementof theprojection 51 with one end of the slot 53 inthe lead carrier tube. The final expelling movement of the parts willcause the feed rod to project through the opening in the writing end ofthe pencil as indicated in Fig. 11.

A Then the movement of the parts is reversed the clutch just describedwill hold the lead carrier tube 54 stationary while the connectionbetween the lead feeding'rod and the helix 4l afforded by the projection51 will causel the rod to be retracted in the carrier tube far enough topermit insertion; of thev lead inthe said tube. Further lretractingmovement will cause the projection 5l on Y the rod to engage the closedend of the slot in the carrier tube and rod and the Vcarrier tube willthereafter move as a unit during the rest of the retracting movement andthe first part of the expelling movement;

It should, perhaps, be made clear that the clutch on the end of thesplit tube is so constructed that when it is allowed to close up afterthe withdrawal therefrom of the lead carrier tube, the interior of theclutch is not brought closely enough into contact with the lead to causethe clutch to pull the lead out` of the carrier tube 54: during theretracting movement of the parts.

While embodiments of the invention have been described in considerabledetail herein, Y

it is notthe desire to be limited to such details except in so far asthey are included in l element mounted in and having a limited movementrelative tothe lead carrier tube, means for driving saidl feeding`element in either direction, and devices including a resilient portionof the carrier tube iiexed byV the final expelling movement of thefeeding element for holding the lead carrier tube against movementduring the first part of the retracting movement of the feeding element,but ineffective to hold the lead carrier tube against further retractivemovement.V

9.. In a mechanical pencil, a pencil body having a ktubular interiorprovided with a shallow spiral groove, ,a wire helixresting in saidgroove and having a part of the diameter of the wire projecting intosaid tubular interior, a lead feedingelement carrying a projectionengaging `with saidk ,projecting portion of the helix, and means foreffecting a relative rotary movement of the feeding elementand helix todrive the feeding element. Y

3. The method ofmaking'the operating helix for a mechanical pencilwhichcomprises cutting a shallow spiral groove on the interior of thebarrel ofthe pencil and threading a Wire helix into said groove by arelative f rotation of said barrel and helix. n

4. In a mechanical pencil," a lead carrier tube, a feed rod in andhaving a limitedsliding movement relative to the carrier tube, meansincluding a head on the feed rod for driving the feed rod in eitherdirection, a

stationary clutch member, an expandible' clutch member carried by theVcarrier tube and expanded by the head on the feed rod to engage thestationary clutch member during the iinal lead feeding movement of therod, said expanded member being held in expanded conditionv during thefirst part of the retracting movement of the feed rod. Y

5. In a mechanical pencil, a leadcarrier tube, a feed rod mounted. inand havingla ec Y.

limited movement'relative tothe lead carrier tube, means including ahelix, a head on the feed rod and a split tube for driving thel feed,rod in either direction, said split tubesignature..

v Y JOSEPH MEILNER.

